The Insect Resistance Of Rice Induced By Elicitor SC-30 And Functional Mechanism

Utilizing chemical elicitors to promote plants’resistance is considered as a promising approach in integrated pest management strategies.In this study,we indentified a new elicitor,SC-30,and investigated the mechanisms underlying SC-30induced rice resistance.We found that SC-30 has no direct toxic effects on rice pest brown planthopper（BPH）Nilaparvata lugens,whereas pretreatment of rice with SC-30 showed negative effects on the survival and development of BPH nymphs and adults,as well as the feeding behavior of gravid BPH female adults,indicating that SC-30effectively enhanced rice resistance against BPH.In addition,SC-30 elicited rice resistances were observed in all tested rice geonotypes（japonica and indica）and herbivore species(BPH and white-backed planthoppers（WBPH）Sogatella furcifera,suggesting that SC-30 can induce a broad spectrum of herbivore resistance in rice.Further studies revealed that SC-30 application altered the biosynthesis of phytohormones（ethylene,salicylic acid and H₂O₂）,the expression of two defense-related genes（OsNPR1 and OsWRKY45）,as well as the production of direct（flavonoids）and indirect（volatiles）defensive compounds in rice.Taken together,these findings suggest that SC-30 promotes the resistance of rice to pests thereby has a potential to be exploited as a chemical elicitor for rice pest management.